Michael J. T. Guy (born 1 April 1943^{[citation needed]}) is a Britishcomputer scientist andmathematician. He is known for early work on computer systems, such as thePhoenix system at theUniversity of Cambridge,^[1] and for contributions tonumber theory,computer algebra, and the theory ofpolyhedra in higher dimensions. He worked closely withJohn Horton Conway, and is the son of Conway's collaboratorRichard K. Guy.

WithConway, Guy found the complete solution to theSoma cube ofPiet Hein.^[2][3] Also with Conway, an enumeration led to the discovery of thegrand antiprism, an unusualuniform polychoron in four dimensions. The two had met atGonville and Caius College, Cambridge, where Guy was an undergraduate student from 1960, and Conway was a graduate student. It was through Michael that Conway met Richard Guy, who would become a co-author of works incombinatorial game theory.^[4] Michael Guy with Conway made numerous particular contributions to geometry, number and game theory, often published in problem selections by Richard Guy. Some of these arerecreational mathematics, others contributions todiscrete mathematics.^[5] They also worked on thesporadic groups.^[6]

Guy began work as a research student ofJ. W. S. Cassels atDepartment of Pure Mathematics and Mathematical Statistics (DPMMS), Cambridge.^[7] He did not complete a Ph.D., but joint work with Cassels produced numerical examples on theHasse principle forcubic surfaces.^[8]

He subsequently went into computer science. He worked on thefiling system forTitan, Cambridge'sAtlas 2,^[9][10] being one of a team of four in one office includingRoger Needham.^[11][12] In working onALGOL 68, he was co-author withStephen R. Bourne ofALGOL 68C.^[13][14]

• Conway, J.H.; Guy, M. J. T. (1965). "Four-Dimensional Archimedean Polytopes".Proceedings of the Colloquium on Convexity at Copenhagen. pp. 38–39.
• Conway, J.H.; Croft, H.T.;Erdos, P.; Guy, M. J. T. (1979). "On the Distribution of Values of Angles Determined by Coplanar Points".Journal of the London Mathematical Society.II (19):137–143.CiteSeerX 10.1.1.210.6483.doi:10.1112/jlms/s2-19.1.137.
• Bremner, Andrew (Tempe, AZ); Goggins, Joseph R. (Girvan); Guy, Michael J. T. (Cambridge); Guy, Richard K. (Calgary, Alta) (2000)."On rational Morley triangles"(PDF).Acta Arithmetica.XCIII (2).{{cite journal}}: CS1 maint: multiple names: authors list (link)

• Conway, John H.; Burgiel, Heidi; Goodman-Strauss, Chaim (2008).The Symmetries of Things.Natick, Massachusetts –Boca Raton, Florida:A K Peters –CRC Press. p. 217.ISBN 978-1-5688-1220-5.

• 1940s births
• Living people
• 20th-century British mathematicians
• Alumni of Gonville and Caius College, Cambridge
• Recreational mathematicians
• Mathematics popularizers
• British computer scientists

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